The UHRF1 Protein Stimulates the Activity and Specificity of the Maintenance DNA Methyltransferase DNMT1 by an Allosteric Mechanism
The UHRF1 Protein Stimulates the Activity and Specificity of the Maintenance DNA Methyltransferase DNMT1 by an Allosteric Mechanism
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DOI：
10.1074/jbc.m113.528893
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发表时间：
2014-02-14
影响因子：
4.8
通讯作者：
Jeltsch, Albert
中科院分区：
文献类型：
--
作者：
Bashtrykov, Pavel;Jankevicius, Gytis;Jeltsch, Albert
泛素样蛋白1（UHRF 1）是一种含有PHD和RING指结构域的蛋白质，是DNA甲基转移酶1（DNMT 1）维持DNA甲基化所必需的。UHRF 1通过其SET和RING相关（SRA）结构域与半甲基化DNA结合的能力将DNMT 1募集到复制的DNA中。在这里，我们证明了UHRF 1也使DNMT 1的活性增加了近5倍。这种刺激是由两种蛋白质通过UHRF 1的SRA结构域和DNMT 1的复制焦点靶向序列结构域的直接相互作用介导的，并且它不需要SRA结构域的DNA结合。通过替换复制焦点靶向序列结构域中的关键残基来破坏DNMT 1和UHRF 1之间的相互作用，导致DNMT 1刺激的强烈降低。此外，与UHRF 1的相互作用增加了DNMT 1对半甲基化CpG位点甲基化的特异性。这些发现表明，除了DNMT 1靶向复制的DNA外，UHRF 1还增加了DNMT 1的活性和特异性，从而对DNA甲基化的维持产生多方面的影响。
The ubiquitin-like, containing PHD and RING finger domains protein 1 (UHRF1) is essential for maintenance DNA methylation by DNA methyltransferase 1 (DNMT1). UHRF1 has been shown to recruit DNMT1 to replicated DNA by the ability of its SET and RING-associated (SRA) domain to bind to hemimethylated DNA. Here, we demonstrate that UHRF1 also increases the activity of DNMT1 by almost 5-fold. This stimulation is mediated by a direct interaction of both proteins through the SRA domain of UHRF1 and the replication focus targeting sequence domain of DNMT1, and it does not require DNA binding by the SRA domain. Disruption of the interaction between DNMT1 and UHRF1 by replacement of key residues in the replication focus targeting sequence domain led to a strong reduction of DNMT1 stimulation. Additionally, the interaction with UHRF1 increased the specificity of DNMT1 for methylation of hemimethylated CpG sites. These findings show that apart from the targeting of DNMT1 to the replicated DNA UHRF1 increases the activity and specificity of DNMT1, thus exerting a multifaceted influence on the maintenance of DNA methylation.